I - Astartes from Cantus Imperialis by Tom Call & The BattleJazz Orchestra

The Adeptus Astartes, or Space Marines, are the genetically enhanced super soldiers of the Imperium of Mankind. Created by the emperor circa
millenium 30, they are superhuman giants, whose enhanced physiology makes them immune to disease, resitant to fatigue, capable of fighting
for days on end, and functionally immortal. They are the Emperor's Angels of Death, descending from the sky in ancient warships to bring
enlightenment to the galaxy, in the name of the Emperor, beloved by all.

Before the Creation of the Astartes, the emperor of Mankind employed his formidable knowledge of science, gene-craft, and psychic mastery to
create twenty demigod-like sons, called 'Primarchs". Into each one he gene-wrought aspects of his own nature, gifted physically, mentally, and
psychically, beyond the scope of human possibility. From the genetic code of each of his Primarch sons, he fashioned twenty unique legions of
astartes, each one genetically molded into the image of their primarch "father".

Armed with his Primarchs and his Legiones Astartes, The Emperor embarked on the Great Crusade, his conquest to reunite the galaxy and the
multitudinous branches of humanity which had been lost during the chaos of the century long "Old Night", during which interstellar travel
became nigh impossible.

The galaxy, rife with hostile xenos species and even hostile branches of humanity, is frought with horrors beyond imagining. The Astartes are the
Emperor's Bulwark against the terror.

After the great triumph on Ullanor, the Emperor revealed his intention to return to Terra, naming his favored Son, Horus Lupercal, Primarch of the
Luna Wolves legion, as Warmaster. Given power and authority over all other Primarchs and Legiones Astartes, the warmaster was to lead the
Great Crusade in the emperor's stead. The naming of one son over the others caused disquet among some primarchs, others exhibiting fierce loyalty
and joy at the elevation of their beloved brother.

It was here, at the height of the great crusade, that the Imperium was at its strongest. It was here that it's downfall began.

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